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41.
Endometrial stem cell transplantation in MPTP‐ exposed primates: an alternative cell source for treatment of Parkinson's disease 下载免费PDF全文
Erin F. Wolff Levent Mutlu Efi E. Massasa John D. Elsworth D. Eugene Redmond Jr. Hugh S. Taylor 《Journal of cellular and molecular medicine》2015,19(1):249-256
Parkinson's disease (PD) is a neurodegenerative disease caused by the loss of dopaminergic neurons in the substantia nigra. Cell‐replacement therapies have emerged as a promising strategy to slow down or replace neuronal loss. Compared to other stem cell types, endometrium‐derived stem cells (EDSCs) are an attractive source of stem cells for cellular therapies because of their ease of collection and vast differentiation potential. Here we demonstrate that endometrium‐derived stem cells may be transplanted into an MPTP exposed monkey model of PD. After injection into the striatum, endometrium‐derived stem cells engrafted, exhibited neuron‐like morphology, expressed tyrosine hydroxylase (TH) and increased the numbers of TH positive cells on the transplanted side and dopamine metabolite concentrations in vivo. Our results suggest that endometrium‐derived stem cells may provide a therapeutic benefit in the primate model of PD and may be used in stem cell based therapies. 相似文献
42.
Celikyurt IK Ulak G Mutlu O Akar FY Mulayim S Erden F Komsuoglu SS 《Life sciences》2012,90(5-6):185-189
AimsThe effect of an antiepileptic drug on cognitive function is of primary importance with respect to the patient's quality of life. Levetiracetam (LEV) is a novel antiepileptic drug used to treat epilepsy, but its effects on spatial and emotional learning and memory are not yet well understood. The goal of our study was to establish the effects of LEV (17 and 54 mg/kg, intraperitoneally (IP)) on spatial memory retrieval in the Morris water maze test and on acquisition and memory formation in the passive avoidance (PA) test in naive mice.Main methodsThe subjects were adult male BALB/c mice. Spatial learning and memory was established with the Morris water maze (MWM) test. The ‘time spent in escape platforms quadrant’ and the ‘distance to platform’ analyses were measured using a video tracking system to determine spatial memory function. Emotional learning and memory were determined with a one-trial, step-through passive avoidance test.Key findingsIn the MWM test, LEV (17 and 54 mg/kg) neither affected the time spent in the target quadrant nor altered the distance to platform. Moreover, LEV had no effect on swim speed. In the PA task, LEV (17 and 54 mg/kg) significantly prolonged retention latency.SignificanceOur results indicate that LEV did not alter spatial memory retrieval in the MWM test, but it did show some ameliorating effects on acquisition and memory formation in the PA test in naive mice. 相似文献
43.
In order to evaluate the allelopathic potential of Nepeta meyeri Benth., the effects of aqueous extracts (0.125, 0.25, 0.5, 1, 2.5 and 5%) prepared from roots and leaves of N. meyeri were studied on the seed germination and seedling growth of several economically important crops (barley, wheat, canola,
safflower, and sunflower). Both the root and leaf extracts of N. meyeri caused a general phytotoxic effect on the seed germination and seedling growth of barley and sunflower at all concentrations.
However, both the root and leaf extracts significantly increased the seedling growth of wheat, especially at the lower concentrations
0.125, 0.25 and 0.5%, whereas the higher concentrations had a neutral effect. The seed germination and the seedling growth
of canola and safflower were also generally improved by both extracts, especially at lower concentrations. However, these
advantages were not observed at higher concentrations, at which the extracts mostly had a phytotoxic effect on canola and
safflower. The Allelopathic activity of N. meyeri depended on whether the extract was derived from the leaf or root parts of the plant. The maximum allelopathic effect occurred
with leaf extracts. The results demonstrate that the aqueous extracts from N. meyeri have allelopathic potential and should be evaluated as an allelopathic species, presenting a risk or advantage to seed germination
and seedling growth of crop or weed plants. 相似文献
44.
A collection of 96 female Turkish fig (Ficus carica L.) accessions was studied to elucidate genetic structure and estimate diversity and genetic similarity distribution among
the female figs present in Turkish genetic resources, using 157 molecular genome markers including 129 sequence-related amplified
polymorphisms, 21 random amplified polymorphic DNAs, and 7 simple-sequence repeats. The plant samples mainly included Turkish
fig collections selected throughout the country over the course of a half-century. Neighbor-joining analysis revealed continuous
dissimilarity range, and it was difficult to classify figs into distinct groups. The principle component analysis produced
similar results. The analysis of molecular variance indicated that 95 and 93% of genetic variation were explained by within
geographic origins and similar fruit rind color, respectively. Sub-structuring Bayesian analysis assigned the 96 female figs
into four sub-populations, and indicated that they were highly related. The corrected allelic pairwise distances among the
six geographic origins were less than 5%. This study suggests that geography- and color-based groups were not genetically
distinct among the Turkish figs. 相似文献
45.
Drought-induced changes in nutrient concentrations and retention in two shallow Mediterranean lakes subjected to different degrees of management 总被引:3,自引:0,他引:3
Arda Özen Burcu Karapınar İsmail Kucuk Erik Jeppesen Meryem Beklioglu 《Hydrobiologia》2010,646(1):61-72
While extensive knowledge exists on the relationship between nutrient loading and nutrient concentrations in lakes in the
cold temperate region, few studies have been conducted in warm lakes, not least in warm arid lakes. This is unfortunate as
a larger proportion of the world’s lakes will be situated in arid climates in the future due to climate change and a larger
proportion will suffer from a higher frequency of intensive drought. We conducted a comprehensive 11–13 year mass balance
study in two interconnected shallow Mediterranean lakes in Turkey, covering a period with substantial changes in climate conditions.
The upstream lake was only affected by natural changes in nutrient loading, while the downstream lake was additionally influenced
by sewage diversion and restoration by fish removal. Contrasting to experience from north temperate lakes we found an increase
in in-lake concentrations of total phosphorus and inorganic nitrogen (ammonia as well as nitrate) in dry years despite lower
external nutrient loading, and submerged macrophytes did not increase the nitrogen retention capacity of the lakes. In contrast,
fish removal modulated the nitrogen concentration as in north temperate lakes, but the effect was not long-lasting. Our results
suggest that climate warming reduces the nutrient retention capacity of shallow lakes in the Mediterranean and exacerbates
eutrophication. Lower thresholds of nutrient loading for shifting turbid shallow lakes to a clear water state are therefore
to be expected in arid zones in a future warmer climate, with important management implications. 相似文献
46.
Kucuk O Sarkar FH Djuric Z Sakr W Pollak MN Khachik F Banerjee M Bertram JS Wood DP 《Experimental biology and medicine (Maywood, N.J.)》2002,227(10):881-885
Epidemiological studies have shown an inverse association between dietary intake of lycopene and prostate cancer risk. We conducted a clinical trial to investigate the biological and clinical effects of lycopene supplementation in patients with localized prostate cancer. Twenty-six men with newly diagnosed prostate cancer were randomly assigned to receive a tomato oleoresin extract containing 30 mg of lycopene (n = 15) or no supplementation (n = 11) for 3 weeks before radical prostatectomy. Biomarkers of cell proliferation and apoptosis were assessed by Western blot analysis in benign and cancerous prostate tissues. Oxidative stress was assessed by measuring the peripheral blood lymphocyte DNA oxidation product 5-hydroxymethyl-deoxyuridine (5-OH-mdU). Usual dietary intake of nutrients was assessed by a food frequency questionnaire at baseline. Prostatectomy specimens were evaluated for pathologic stage, Gleason score, volume of cancer, and extent of high-grade prostatic intraepithelial neoplasia. Plasma levels of lycopene, insulin-like growth factor-1, insulin-like growth factor binding protein-3, and prostate-specific antigen were measured at baseline and after 3 weeks of supplementation or observation. After intervention, subjects in the intervention group had smaller tumors (80% vs 45%, less than 4 ml), less involvement of surgical margins and/or extra-prostatic tissues with cancer (73% vs 18%, organ-confined disease), and less diffuse involvement of the prostate by high-grade prostatic intraepithelial neoplasia (33% vs 0%, focal involvement) compared with subjects in the control group. Mean plasma prostate-specific antigen levels were lower in the intervention group compared with the control group. This pilot study suggests that lycopene may have beneficial effects in prostate cancer. Larger clinical trials are warranted to investigate the potential preventive and/or therapeutic role of lycopene in prostate cancer. 相似文献
47.
Plant aspartic proteinases: enzymes on the way to a function 总被引:7,自引:0,他引:7
Plant aspartic proteinases have been characterized from seeds, flowers and leaves of a number of different species. The enzymes are generally either monomeric or heterodimeric, containing two peptides processed from the same precursor protein. The plant enzymes, like their mammalian and microbial counterparts, are active at acidic pH and inhibited by a class specific inhibitor pepstatin A. Plant aspartic proteinases are generally either secreted or targeted to the vacuolar/protein storage body compartment. The primary sequences of many of these enzymes have been determined and are very homologous with each other as well as with enzymes from mammalian and microbial origins. Plant aspartic proteinases, however, have a very unique plant specific region, which is not found in mammalian, microbial, or viral aspartic proteinases. The function of this region has not been elucidated. A role for these plant enzymes in protein processing or degradation has been proposed, however, more studies are required to confirm their in vivo functions. Recent intriguing results suggest possible roles for these enzymes in programmed cell-death of tissues and in pathogen resistance. 相似文献
48.
Robin D. Couch Karl Navarro Masoumeh Sikaroodi Pat Gillevet Christopher B. Forsyth Ece Mutlu Phillip A. Engen Ali Keshavarzian 《PloS one》2013,8(11)
Recent studies have illustrated the importance of the microbiota in maintaining a healthy state, as well as promoting disease states. The intestinal microbiota exerts its effects primarily through its metabolites, and metabolomics investigations have begun to evaluate the diagnostic and health implications of volatile organic compounds (VOCs) isolated from human feces, enabled by specialized sampling methods such as headspace solid-phase microextraction (hSPME). The approach to stool sample collection is an important consideration that could potentially introduce bias and affect the outcome of a fecal metagenomic and metabolomic investigation. To address this concern, a comparison of endoscopically collected (in vivo) and home collected (ex vivo) fecal samples was performed, revealing slight variability in the derived microbiomes. In contrast, the VOC metabolomes differ widely between the home collected and endoscopy collected samples. Additionally, as the VOC extraction profile is hyperbolic, with short extraction durations more vulnerable to variation than extractions continued to equilibrium, a second goal of our investigation was to ascertain if hSPME-based fecal metabolomics studies might be biased by the extraction duration employed. As anticipated, prolonged extraction (18 hours) results in the identification of considerably more metabolites than short (20 minute) extractions. A comparison of the metabolomes reveals several analytes deemed unique to a cohort with the 20 minute extraction, but found common to both cohorts when the VOC extraction was performed for 18 hours. Moreover, numerous analytes perceived to have significant fold change with a 20 minute extraction were found insignificant in fold change with the prolonged extraction, underscoring the potential for bias associated with a 20 minute hSPME. 相似文献
49.
50.
Nagothu KK Rishi AK Jaszewski R Kucuk O Majumdar AP 《American journal of physiology. Gastrointestinal and liver physiology》2004,287(3):G541-G546
Although accumulating evidence suggests a chemopreventive role for folic acid (FA) in colorectal carcinogenesis, the underlying mechanisms are largely unknown. Previously, we reported that supplemental FA inhibits the expression and activation of epidermal growth factor receptor (EGFR) in colon cancer cell lines. To determine the mechanism(s) by which FA affects EGFR function, we have examined whether and to what extent supplemental FA or its metabolites 5-methyltetrahydrofolate (MTF), dihydrofolate (DF), and tetrahydrofolate (TF) will modulate basal and serum-induced activation of the EGFR promoter in the HCT-116 colon cancer cell line. HCT-116 cells were preincubated with or without (control) FA or one of its metabolites (10 microg/ml) for 48 h, transfected with the EGFR promoter luciferase reporter construct, and incubated for 48 h with FA, DF, TF, or 5-MTF in the absence or presence of 10% FBS. Supplemental FA as well as its metabolites markedly inhibited EGFR promoter activity and its methylation status. Exposure of the cells to 10% FBS caused a marked stimulation of EGFR promoter activity and its expression, both of which were greatly abrogated by supplemental FA and 5-MTF. In contrast, serum-induced activation of c-fos promoter activity was unaffected by 5-MTF. The 5-MTF-induced inhibition of serum-mediated stimulation of EGFR promoter activity and EGFR expression was reversed when methylation was inhibited by 5-aza-2'-deoxycytidine. Our data suggest that FA and its metabolite 5-MTF inhibit EGFR promoter activity in colon cancer cells by enhancing methylation. This could partly be responsible for FA-mediated inhibition of growth-related processes in colorectal neoplasia. 相似文献